Gene Expression and Cellular Specialization

In a repressible operon, transcription is usually ____

• off

• on

In an inducible operon, transcription is usually ____

• off

• on

Select the three parts of an operon:

• Promoter

• Genes

• Operator

• Cooperator

• Transducer

Does the DNA loosen or tighten with acetylation?

• tighten

• loosen

• does nothing

Does the DNA loosen or tighten with methylation?

• tighten

• loosen

• does nothing

How do microRNAs and small interfering RNAs affect gene expression? Select all that apply.

• Bind to mRNA

• Block translation

• Degrade mRNA

• Make gene expression occur at a faster rate

Why is apoptosis important for morphogenesis? Select all that apply.

• Allows limbs to form

• Allows webbing between digits to be removed

• Allows organ development

• Causes cancer in utero

A protein that binds to the operator and blocks the RNA polymerase

• regulator
• repressor
• activator
• corepressor

The "on/off" switch for an operon is called the

• promoter
• repressor
• operator
• gene

In the lac operon the inducer is

• allolactose

• glucose

• galactose

• all of the above